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charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Mar 30, 2023 at 07:17:59PM +0000, Yosry Ahmed wrote: > In workingset_refault(), we call > mem_cgroup_flush_stats_atomic_ratelimited() to read accurate stats > within an RCU read section and with sleeping disallowed. Move the > call above the RCU read section to make it non-atomic. >=20 > Flushing is an expensive operation that scales with the number of cpus > and the number of cgroups in the system, so avoid doing it atomically > where possible. I understand why one does not process the whole flushing load in one go in general. However, I remember there were reports of workingset_refault() being sensitive to latencies (hence the ratelimited call was created). Is there any consideration on impact of this here? (Or are there other cond_resched() precendents on this path? Should it be mentioned like in the vmscan (7/8) commit?) Thanks, Michal --qfkseaqkxxqkcz24 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTrXXag4J0QvXXBmkMkDQmsBEOquQUCZCxV7gAKCRAkDQmsBEOq uUD+AQD8wXXi9jmmMAZsQDelWPQkkod/PwIlrMWJ7mxxhDrGEwEAqpLPmU1ZnE0x eJvubQemadydJAWDGZe8mox2qJ3iLAY= =AwCK -----END PGP SIGNATURE----- --qfkseaqkxxqkcz24--